Transformer construction



Dec. 6, 1927. 1,651,713

I J. KARAS mmsvonmsn cous-rnucnom Fild Jan.28, 1924 INVENTOR a Xvxc msPatented Dec. 6, 1927.

UNITED STATES JOSEPH KARAS, oF CHICAGo, ILLINOIS.

TRANSFORMER CONSTRUCTION.

Application filed January 28, 1924.

a transformer construction of the character described in which a novelmeans is employed for closely binding the superimposed lamina ofthelaminated core 111 close engagement with one another, thereby assurmg auniform and intense tiel d through and about the core.

A further object of my invention isto provide a device of the typedescribed in which the necessity of cutting away portions of the corefor the introduction of binding bolts or rivets is entirely precluded.This structure assists materially in supporting maximum strength in themagnetic field about the core.

A further object of my invention is to provide a device of the typedescribed in which the core as Well as the primary and secondarywindings are entirely encased and in which novel means is employed forsupporting the core and windings at a spaced distance from the Walls ofthe casing.

A further object of my invention is to provide a device of the typedescribed in which the end pieces forming a part of the transformercasing perform a dual function, i. e., that of binding the lamina of thecore together and of supporting the core and windings free of contactwith the metal walls of the casing.

A further object of my invention is to provide a device of the typedescribed which is compact in form, durable, and thoroughly practicalcommercially.

Other objects and advantages will appear in the following specification,and the novel features of the invention will be particularly pointed outin the appended claims.

My invention is illustrated in the accompanying drawings forming part ofthis ap plicatiou, in which Figure 1 is a side elevation of anembodiment of my invention,

Figure 2 is an end elevation of the mechanism illustrated in Figure 1,

Figure 3 is a. sectional View along the line 3-3 of Figure 1, and aFigure 4 is a sect'onal view along the line H of Figure 2.

In carrying out my invention I make use of a laminated core 1 comprisinga plurality Serial N0. 688,925.

of superimposed lamina of soft sheet iron. The core 1 is substantiallyrectangular in contour and nearly equilateral in cross section.

A primary and a secondary winding, one concentric with the other aredisposed as shown at 2 upon one of the longer branches 3 of the core 1.

Means for encasing and supporting the core 1 with its windings 2provided in a metal cylinder 4 and a pair of end closures or end plates5 arranged to partially encompass the peripheral edges of the cylinder4.

These end plates 5 I deem of great importance, since their use enablesone to dispense with certain disadvantages ordinarily found intransformers employing laminated cores.

From an inspection of Figure 4 it will be noted that each of the endplates 5 is provided with transversely disposed outwardly extendingsubstantially horizontal indentures 6. It will be further noted that theindentures are of lesser width at the innermost or remote end than atthat portion which merges with the vertical face of the end plates. Thisconstruction necessarily provides inclined side walls 7 forming a partof the indentures.

The width of the indentures 6 at the remote ends thereof is slightlyless than the thickness of the superimposed lamina forming the core 1when fully compressed.

The rods 8 are projected through the upper and lower parts of the endplates 5 and serve to provide a means for drawing the end plates towardone another and consequently the core 1 toward the innermost end of theindentures 6 in the plates, whereby the core 1 is maintained in atightly com pressed condition.

The grip of the plates 5 upon the core 1 serves also to maintain thecore 1 against lateral movement and therefore keeps the windin 2 out ofengagement with the cylinder 4-.

Suitable binding terminals 9 are provided for connection of the windings2 to extraneous apparatus.

Supporting members 10 are formed. integral with the end plates 5 andserve to provide adequate means for fixing the transformer to asupporting surface or panel.

From the foregoing description of the various parts of my invention, itwill be noted that- I have provided in a t ansformer construction acasing in which the end plates forming part thereof perform a dualfunction and entirely preclude the disadvantages brought about inirregular magnetic flux or tield structure usually found in 'anstormershaving a core of irregular or mutilated character.

I claim:

1. In a transformer of the character described having a core comprisinga plurality of superimposed lamina, of a pair of 00- operatingsupporting plates each having an indentiire for partially receiving theopposite ends respectively of said core, said plates having theindentures therein formed with inclined side walls, whereby said laminaare forced into close engagement with one another as said plates aredrawn toward one another.

2. In a tlflllSfOllllGl oi? the character described having a core crunjn'ising a plurality of superimposed lamina of a pair of (:0- operatingdiametricallv disposed end. snpporting plates each having an indenturefor partially receiving the opposite ends respectively of said core,said plates having theindentures therein formed with inclined side wallswhereby said lamina are forced into close engagement with one anothersaid plates are drawn toward. one another. and means for drawing said.plates toward one another.

A transformer of the character described compr'sing a plurality ofsuperimposed magnetizable lamina, current conducting coils wound uponsaid lamina, a cylindrical shell encompassing said lamina and said coilsa pair of end plates for the ends of said shell, said end plates havingindcntnrcs in the inner walls thereof providcd with inclined side walls,the width of Eiilltl indentures being less at the inner ends than thethickness oil said superimposed lan'iina when uncompressed and means forc.-..l1'l f said end plates toward said core and toward. said shellwhereby the lamina will be tightly compressed and held against movementwith respect to said shell.

i. A transformer of the character de scribed, comprising a plurality ofsuperimposed n Inetizable lamina, a current coninding disposed upon saidlamina,

ducting w a tubular shell encompassing said lamina and said winding. apair of end. plates for the ends of said shell, said end plates eachhaving an indcnturc in the inner wall thereor provided with inclinedside walls, the width of said indentures being less at the inner endsthan the thickness of said superimposed lamina when uncompressed, andmeans for drawing said end plates toward said core and toward said shellwhereby the l: inina will be tightly compressed and held againstmovement with respect to the shell.

JOSEPH KARAS.

